/**
 * Copyright (C) 2010, 2011 Neofonie GmbH
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package eu.dicodeproject.analysis.util;

import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Calendar;

/**
 * @author jakob
 */
public class TimeUtil {

  private DateFormat dateFormat = new SimpleDateFormat("yyyyMMdd");

  public String getPastDate(int daysBack) {
    Calendar cal = Calendar.getInstance();
    cal.set(Calendar.HOUR_OF_DAY, 0);
    cal.set(Calendar.MINUTE, 0);
    cal.set(Calendar.SECOND, 0);
    cal.set(Calendar.MILLISECOND, 0);

    if (daysBack != 0) {
      cal.add(Calendar.DAY_OF_MONTH, daysBack * -1);
    }

    return dateFormat.format(cal.getTime());
  }

}
